A DC-DC converter has two switch elements which are cascode-coupled between a power supply and the ground and performs DC-DC conversion by turning the two switch elements on and off in a complementary manner. As these two switch elements, N-channel metal-oxide semiconductor field effect transistors (MOSFETs) are used. An N-channel MOSFET has a lower on-resistance and a smaller parasitic capacitance (a smaller amount of capacitance charging and discharging) than a p-channel MOSFET.
Related techniques are disclosed in Japanese Laid-open Patent Publication No. 2010-4198 and a non-patent document: V. Pinon et al. (STMicroelectronics), “A Single-Chip WCDMA Envelope Reconstruction LDMOS PA with 130 MHz Switched-Mode Power Supply”, ISSCC Dig. Tech. Papers, pp. 564-565, February 2008.